Procollagen II C propeptide level in the synovial fluid as a predictor of radiographic progression in early knee osteoarthritis.

OBJECTIVE: To investigate the prognostic value of procollagen type II carboxy-terminal propeptide (PIICP) level in synovial fluid in relation to early tibiofemoral joint osteoarthritis (OA). METHODS: Data were collected on 172 women (age 40 to 59 years) who had knee pain and tibiofemoral joint OA in the early stage. Standing semiflexed knee radiographs were obtained by fluoroscopy at baseline and at four year follow up and a computerised, magnification corrected measurement system was applied to measurement of minimal joint space width in the tibiofemoral compartment. Synovial fluid sampling was performed at baseline and at the four year follow up. Levels of PIICP in the synovial fluid were measured by enzyme immunoassay. The outcome measures were assessed by radiographic joint space narrowing (JSN) in the tibiofemoral joints over four years. Multiple linear regression analyses were used to examine the relation between radiographic JSN and synovial fluid level of PIICP. RESULTS: The number of women available at both baseline and at four year follow up was 110. The average of radiographic JSN over four years was 0.53 mm (range 0.00-2.01). Body mass index showed a slightly positive association with baseline PIICP level. In multiple linear regression analyses adjusted for age and body mass index, radiographic JSN over four years had a direct positive correlation with baseline PIICP level (r=0.395; 95% confidence interval (95% CI) 0.231 to 0.529; p<0.001). CONCLUSION: In a four year prospective study of women, quantification of synovial fluid PIICP was able to predict subsequent radiographic progression in early tibiofemoral joint OA.

Intramolecular energy transfer processes in binuclear Re-Os complexes.

A series of bimetallic complexes of general formula [(phen)Re(CO)(3)LOs(trpy)(bpy)](3+) (bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, trpy = 2,2':6',2' '-terpyridine, and L = 4,4'-bipyridine (4,4'-bpy), trans-1,2-bis(4-pyridyl)ethylene (t-bpe), or 1,2-bis(4-pyridyl)ethane (bpa)) and the model mononuclear species [(phen)Re(CO)(3)L](+) and [Os(trpy)(bpy)L](2+) have been synthesized and their photophysical and photochemical properties studied. In the binuclear species an efficient Re(I)-Os(II) energy transfer is observed, which is analyzed in terms of Förster theory. In the binuclear [(phen)Re(CO)(3)(t-bpe)Os(trpy)(bpy)](3+) complex, the trans to cis isomerization of the coordinated t-bpe ligand, characteristic of the [(phen)Re(CO)(3)(t-bpe)](+) subunit, is inhibited by competitive intramolecular energy transfer.

Trapezius interposition of a distal third clavicular fracture in a child: A case report.

We report an 11-year-old child with fracture of the distal clavicle who was denied conservative treatment because the medial end of the clavicle was anchored into the trapezius muscle fiber by an extreme posterior displacement. Surgical reduction was indicated.

Influence of anteroposterior and mediolateral instability on range of motion after total knee arthroplasty: an ultrasonographic study.

Ultrasonographically, the femoral component and the tibial plate of total knee prostheses are strongly echogenic, while the high-density polyethylene insert is hypoechoic. This study evaluated the influence of mediolateral and anteroposterior stability after total knee arthroplasty (TKA) on range of motion using real-time monitoring with ultrasound. Mediolateral stress translation, which is increased by horizontal resection of more bone at the ends of the femur or tibia for easy prosthesis implantation, was examined on coronal scans at the level of the collateral ligaments. Anteroposterior drawer was examined on sagittal scans at the level of the patellar tendon. Mediolateral translation (0-10 mm; mean 2.24 mm) did not correlate with range of motion, while anteroposterior drawer (2-10 mm, mean 5.05 mm) correlated well with range of motion. These ultrasonographic findings suggest that horizontal over-resection of the ends of the femur and tibia contributed to joint laxity, which would not result in better ROM. Rollback and sliding of the femoral component on the tibia, which is believed to be correlated with anteroposterior drawer, may be important in achieving better range of motion and obtaining excellent results in TKA.

Local drug delivery system using ceramics: vacuum method for impregnating a chemotherapeutic agent into a porous hydroxyapatite block.

We performed an experimental study on a new drug delivery system that employs a porous hydroxyapatite block (HAb) (composition: Ca10(PO4)6(OH)2)) to conduct sustained release of a chemotherapeutic agent. To confirm penetration of the agent into the HAb (2 cm3), an aqueous solution containing eosin dye was used at various vacuum pressures. To estimate the storage capacity of the HAb, blocks were weighed before and after being impregnated with the aqueous dye solutions, and the capacity of the block was calculated from the increase in weight after vacuum. In this slow-release study using vacuum, the anti-cancer drug methotrexate (MTX) was used in vitro. Four HAb (1 cm3) containing different concentrations of MTX, ranging from 1.22 to 2.38 mg per block, were studied. All were found to release the drug, maintaining a mean concentration of 0.22 to 0.32 microg/ml even after twelve days. This concentration is high enough to be effective against tumor cells. The results suggest that HAb impregnated with a chemotherapeutic agent using a simple vacuum system may serve as a valuable new method of administering local chemotherapy, primarily when used as a strut graft for bone defects. This new drug delivery system can also be used as an adjuvant material in extended curettage, which can also discourage recurrence of benign tumors without any risk of systemic toxicity.

Abscess formation as a complication caused by postoperative osteomyelitis of the femur.

We report an unusual case of a giant femoral abscess caused by postoperative osteomyelitis after treating a fracture of the femoral shaft. The patient ignored it until the abscess began to interfere with knee flexion, but no symptoms of inflammation such as fever, pain or abnormal laboratory values were found. Within the marrow cavity, many plasma cells produced immunoglobulins G and M, and the level of these substances in the abscess fluid connected to the bony focus were higher than the serum levels. It was concluded that the inflammation in this case signified a peculiarity in a primarily chronic process.

Antibiotic-loaded porous hydroxyapatite blocks for the treatment of osteomyelitis and postoperative infection. A preliminary report.

Hydroxyapatite blocks (HAB) can be used to administer antibiotics or anticancer drugs because its porous structure allows the gradual administration of the pharmacologic agents. A novel drug delivery system using hydroxyapatite blocks was developed for osteomyelitis and postoperative infections occurring after joint replacement. To load the antibiotics, hydroxyapatite blocks were mixed with an antibiotic solution and centrifuged at 1500 rpm for 15 minutes or decompressed in vacuum container at 5 to 10 in. Hg for 20 minutes. Fifteen patients with osteomyelitis including one with tuberculosis and four with infections subsequent to joint replacement were treated with antibiotic-loaded hydroxyapatite blocks in combination with intravenous injection. Except in one case, all of the foci had completely healed at follow-up (range: 13 to 71 months; average: 39.7 months). These new methods are simple and can safely treat osteomyelitis in a one-stage operation.

Exposure of the hip by anterior osteotomy of the greater trochanter.

A new exposure for the direct lateral approach to the hip through the gluteus medius by anterior half osteotomy of the greater trochanter is described. The skin incision is made with the greater trochanter longitudinally at its midpoint and extends parallel to the shaft of the femur along its anterior border. The anterior two thirds of the tendinous gluteus medius muscle is divided. The incision continues to the middle of the greater trochanter and through the distal half of the vastus lateralis muscle. An anterior thin slice osteotomy of the greater trochanter is performed. The gluteus minimus is exposed and split in the line of its fibers or detached from the greater trochanter and the acetabular roof is exposed. In order to provide a wide exposure, a Charnley transverse retractor is used and a Calipers Dual Pin Retractor is inserted over the edge of acetabulum by elevating the soft tissues from the ilium. The Calipers Dual Pin Retractor is used to precisely position the prosthesis in an anatomic and functional position and eliminate leg length discrepancy.

Analysis of rising from a chair after total knee arthroplasty.

The relationship between the range of motion following total knee arthroplasty (TKA) and the height of chairs when rising from a seated position was analyzed. Forty-six TKA subjects were evaluated; 16 had osteoarthritis, 30 had rheumatoid arthritis. Subjects were divided into two groups based on their degree of knee flexion (average: 96.0 degrees; range: 75 degrees to 135 degrees; group 1 contained 24 subjects with < 100 degrees of flexion and group 2 contained 22 subjects with > 100 degrees of flexion) in order to evaluate the acceptable knee flexion angle required for comfortably rising from a chair. To evaluate the flexion-extension angle of the knee and hip joints, three goniometers, a large reaction force plate, and a switch sensor on the chair surface to detect the initiation of rising were used. One chair had a height equal to the subjects' lower leg length, while the height of the second chair was 120% of the subjects' lower leg length. Analysis showed that TKA patients with less knee flexion (< 100 degrees) required a high angular velocity of the hip and excessive swing velocity to lift the trunk forward than did those with a larger degree of knee flexion (> 100 degrees). We concluded that a minimum of 100 degrees of postoperative flexion is desired and that a higher chair is more suitable for TKA patients.

Meniscal cyst in the posterior intercondylar space found by magnetic resonance imaging.

We report a rare case of meniscal cyst from the posterior horn of the lateral meniscus, extending in the posterior intercondylar space of the right knee of a 15-year-old boy, in whom magnetic resonance imaging was very useful for evaluation. A cyst in this location has not been reported previously. The cyst was removed surgically, while preserving the lateral meniscus. A good result was obtained, and no recurrence has been seen in 12 months.

Quantitative analysis of hyaluronan in the synovial tissues of patients with joint disorders.

Quantitative analysis of hyaluronan (hyaluronic acid; HA) in the synovial tissues of patients with joint disorders were performed. HA was found not only in the synovial intimal cells and matrices, but also especially in the alveolar lymphoid follicles and connective tissues surrounding blood vessels in the inflammatory granular synovium which formed the pannus. HA levels in the synovium of patients with rheumatoid arthritis (RA) (459.0+/-66.2 microg/g) where shown to be higher than those in patients with osteoarthritis (246.9+/-34.8 microg/g) and traumatic injury (227.7+/-35.4 microg/g). It follows from the present findings, HA in the synovium might contribute to the high amounts of serum levels of HA in patients with rheumatoid arthritis.

Synthesis of antibiotic-loaded interporous hydroxyapatite blocks by vacuum method and in vitro drug release testing.

Interporous hydroxyapatite ceramic (Ca10(PO4)6(OH)2) has excellent bio-compatibility and interlinked pore structure, antibiotics could be loaded into pores in vacuum system. To confirm penetration of the agent to the HAb (2 cm3 cubic block), the aminoglycoside antibiotic (Isepamicin Sulfate; ISP) dissolved in eosin dye at various vacuum pressures. In ISP slow release study, the blocks were placed in 5 ml of PBS at a temperature of 37 degrees C. The PBS was replaced every 48 h and samples containing released ISP were stored until assay. All were found to release the drug maintaining a mean concentration of 0.41 microg ml(-1) even after 18 days of nine exchanges. This concentration of antibiotic exceeded the minimum inhibitory concentration against the common causative organisms of osteomyelitis. The results suggest that HAb impregnated with antibiotics using a simple vacuum system may serve as a valuable new method of administering local chemotherapy, primarily when used as a strut graft for bone defects.

Development of porous apatite ceramic for local delivery of chemotherapeutic agents.

An experimental study was conducted on a drug delivery system (DDS), using porous apatite ceramics (PAC): hydroxyapatite block (HAb) [Ca10(PO4)6(OH)2] having a porosity of 35-48% and pore size range of 50-300 microm, and beta-tricalcium phosphate block (TCP) [Ca3(PO4)2] having a porosity of 75-80% and pore size range of 100-400 microm, for sustained release of a chemotherapeutic agent. Methotrexate (MTX) was loaded in the pores of PAC blocks by centrifuging the blocks in MTX solution. Impregnation of MTX in PAC blocks (1 cm3) was confirmed by a magnetic resonance imaging (MRI) study using Gadolinium-DTPA enhancement. The MRI showed high signal intensity in the PAC, which was confirmed by dye loading into the pores. To estimate the MTX-releasing capability of the PAC, the blocks were stored in 3 mL of phosphate-buffered saline (PBS) at 37 degrees C and the PBS was replaced every 48 h. The amount of MTX released was assayed by high-performance liquid chromatography. This study showed that MTX-impregnated PAC (0.63-2.25 mg/block) released the drug in a steady manner and maintained its concentration (0.1-1.0 microg/mL) up to 12 days. This concentration is high enough to be effective against tumor cells. Chemotherapeutic agent-impregnated PAC, prepared by simple centrifugation, could be a valuable form of local chemotherapy when used as a strut graft to repair bone defects. This new DDS material could also be used as an adjuvant to extended curettage and provide a means to reduce the recurrence of tumors without risk of systemic toxicity.

The function of posterior tilt of the tibial component following posterior cruciate ligament-retaining total knee arthroplasty.

To increase the range of motion in the knee, posterior cruciate ligament-retaining total knee arthroplasty (TKA), which has a roll back (RB) mechanism, is used. The roll back mechanism is the complex movement of the femoral condyles relative to the tibial plateau, which results in translation of the tibiofemoral contact point posteriorly as the knee is flexed. This study was undertaken to assess the function of the posterior cruciate ligament (PCL) and posterior tibial tilt following PCL-retaining TKA. Eleven fresh-frozen cadaveric normal lower extremity specimens (average age: 75.4 years; range: 69 to 88 years) were obtained for this study. The test was performed on a loading frame after specimen preparation. The calcaneal bone was fixed on the rigid frame. A load of 9.5 kg was applied perpendicularly by the moving frame to femoral head through four casters. PCL strain and RB were measured before and following TKA by changing the posterior tilt of tibial component and the external rotation of femoral component. PCL strain at 105 degrees flexion in the 0 degree posterior tilt group (3.3% +/- 2.4%) was decreased in the 10 degrees posterior tilt group (0.6% +/- 0.5%), and this decrease was statistically significant (p < 0.05). RB was measured as anterior-posterior translation by using an arthroscopic probe. After TKA, RB was decreased in the medial compartment but was increased in the lateral component. These different movements of the tibiofemoral contact points consequently caused rotation in the flexion position. Posterior tilt of the tibial component decreased the efficiency of the PCL's function. Retaining the PCL physically is not the same as preserving the function of the PCL because of the lack of the ACL, the change of the joint line, the differences in articular geometry, and the balance of the ligaments.

Antibiotic-loaded hydroxyapatite blocks in the treatment of experimental osteomyelitis in rats.

A novel drug delivery system for osteomyelitis was developed in which a porous hydroxyapatite block (HAB) is loaded with antibiotic by a centrifugation method. In this study, implantation of HABs loaded with the aminoglycoside antibiotic, arbekacin, were tested in established Staphylococcus aureus osteomyelitis in the proximal tibia of rats after debridement of the marrow cavity. The animals were observed for radiographic signs of infection and tissue was examined histologically. The infections were also evaluated by bone cultures. Bacterial counts were statistically lower in rats implanted with an antibiotic-loaded HAB than in those given a drug-free HAB. Radiographical and histological observations also showed beneficial effects of the antibiotic-loaded implant. The results suggest that the centrifugation method for loading HABs provides a simple drug delivery system. These antibiotic-loaded HABs may be useful for filling grafts in osteomyelitis.

A simple method of intraoperative limb length measurement in total hip arthroplasty.

The equalization of leg-length discrepancy during total hip arthroplasty can be achieved through the use of a simple measuring device, the Calipers Dual Pin Retractor. During total hip arthroplasty a stable reference point must be established to determine leg-length changes. The Calipers Dual Pin Retractor was developed to establish a fixed point on the pelvis, which would remain constant throughout the procedure, from which the distance to the trochanteric area could be measured prior to the dislocation of the hip. This measurement is then used to aid in the proper placement of the femoral components.

A study of the arterial supply of the human acetabulum using a corrosion casting method.

This anatomical study concerns the arterial supply of the human acetabulum. The purpose is to contribute to prevention of postoperative necrosis of the acetabular bone fragment after rotational acetabular osteotomy (RAO). The arterial supply of the acetabulum was determined using a corrosion casting method. The acetabular branch of the obturator artery supplies the acetabulum through the acetabular notch. The pubic branches supply the pelvic surface of the acetabulum. Deep branches of the superior gluteal artery supply the superior region and the inferior gluteal artery supplies the postero-inferior region. From these results, we recognized that the important artery for achieving successful RAO is the acetabular branch of the obturator artery that supplies the acetabulum through the acetabular notch.

The sustained release of antibiotic from freeze-dried fibrin-antibiotic compound and efficacies in a rat model of osteomyelitis.

The kinetics of drug release from fibrin adhesive agent (consisting of fibrinogen, factor 8, thrombin, aportinin and calcium chloride)-antibiotic compound and efficacy on rat experimental osteomyelitis were studied. To enhance the slow release activities of antibiotic, a mixture of fibrin clots was freeze-dried. Effects of freeze-drying were to make a fibrin clot an interlinked pore and to increase crosslinking rate containing an antibiotic. A diffusion test from aminoglycoside (Arbekacin Sulfate: 200 mg) compound was carried out. In vitro study freeze-dried antibiotic compound (FFAC: 1 cm3) was placed in saline (3 ml). The saline was replaced every 48 h and the previous solution was stored at -45 degrees C until assay. The result was that a concentration of 0.4 mg/l, sufficiently high to control Staphylococcus aureus strain IM2-42, was maintained within nine exchanges of saline after 18 days. In vivo animal experiments, FFAC (2 x 2 x 3 mm) were tested in rats with established Staphylococcus aureus osteomyelitis in the proximal tibia. The animals were observed for radiographic signs of infection and tissue was examined histopathologically. Bacterial counts by bone cultures were statistically lower in rats implanted with FFAC than in those only given a drug-free FFC and curettage. Radiographical and histological observations also showed beneficial effects of the FFAC. The results suggest that the FFAC provide a simple drug delivery system, and may be a promising alternative treatment for osteomyelitis.

Indigenous bacterial flora of medicinal leeches and their susceptibilities to 15 antimicrobial agents.

Surface bacterial flora, as well as homogenates, of medical leeches, Hirudo medicinalis and Hirudinaria manillensis, were surveyed and the susceptibility of these isolates to 15 antimicrobial agents was examined. Aeromonas spp. were isolated from all leeches, and Pseudomonas fluorescens and other glucose-non-fermenting gram-negative rods (NF-GNR) were frequent isolates. Isolates were highly resistant to cephalosporins but susceptible to carbapenems, aminoglycosides and ofloxacin. The results indicate that prophylaxis with antimicrobial agents active against Aeromonas spp. and NF-GNR is necessary to avoid opportunist infections caused by indigenous leech flora during medical leech therapy on immunocompromised patients.

Sustained release of adriamycin from implanted hydroxyapatite blocks for the treatment of experimental osteogenic sarcoma in mice.

A sustained-release drug delivery system was developed using a hydroxyapatite (HA) block loaded with adriamycin (ADR) by cenrifugation. Release of ADR was sustained for 66 days in vitro and for 4 weeks in vivo following intramuscular implantation in mice. ADR concentrations in plasma, liver, and kidney were from 0.25% to 10% of that at the implantation site. ADR-HA blocks implanted into osteogenic sarcomas in mice markedly inhibited tumor growth. This drug delivery system provides sustained release of the cancer chemotherapeutic agent and may prove useful for treating malignant tumours while minimising systemic side effects.